GISS 11ka abrupt climate change experiment 969a "Cold North Atlantic experiment"
(Control Run 822D)

GENERAL INFORMATION
Published reference describing model and control run
Hansen, J., Russell, G., Rind, D., Stone, P., Lacis, A., Lebedeff, S., 
Reudy, R., and Travis, L., Efficient three-dimensional global models 
for climate studies, Mon. Wea. Rev., 111, 609-662, 1983.

Published reference describing experiment
This experiment published as "11 kC" (control as "0 kW") in Rind, D.,
Peteet, D., Broecker, W., McIntyre, A. and Ruddiman, W. 
The impact of cold North Atlantic sea surface temperatures on climate: 
implications for the Younger Dryas cooling (11-10k). 
Climate Dynamics 1, 3-33, 1986.

This experiment published as "C" (control as "A") in Overpeck, J.T., 
Peterson, L.C., Kipp, N. Imbrie, J and Rind D. 
Climate change in the circum-North Atlantic region during the last 
deglaciation. Nature 338, p. 553-557, 1989.

Version of model run and date run	Model II, 19?? 
Time step(s) for model and submodules	15 minutes for atmosphere
	1 hour for surface fluxes
Time interval used to store results 	monthly
Seasonal cycle activated	yes
Diurnal cycle activated	yes
Interactive surface ocean model (type)	none, fixed SSTs
Length of model experiment	five years control, experiment
Number of years in average	four years (2-5) experiment
	three years (3-5) control
Solar constant	1367 W/m2
Orbital parameters	11 ka after Berger, 1978
Eccentricity:	0.0195 	(0.0167	control)
Obliquity:	24.20	(23.44		control)
Longitude of perihelion (w): 	278.41	(102.04	control)
Trace Gas Concentrations
CO2 concentration 	315 ppm (same as control)
CH4 concentration 	295 ppm (same as control)
N2O	1400 ppm (same as control)
Grid description/spatial resolution	"8°x10°" (24 latitude by 36 longitude)
	7.826°x10° with half grid boxes (3.913°) at 
	each pole
	(See Postscript file: 
	model_II_8x10grid.ps)
Vertical resolution	9 layers 
	(1 boundary, 1 stratosphere)
Surface elevation	modern, with sea-level drop and 11ka 	land ice 
Surface type/characterists and fraction 	11ka land ice (Denton and 
Hughes, 1981)
 vegetation	modern, extrapolated to lowered sea 
	level and replaced with ice where 
	specified by Denton and Hughes, 1981
Soil properties specified as function of  vegetation 
(Table 6, Hansen et al., 1983)
Specified Fields modern sea surface temperatures, except in region of 
N. Atlantic north of 25°N, where they were set to CLIMAP 18ka values 
(CLIMAP, 1981)
SUMMARY GLOBAL OUTPUT (MEAN ANNUAL AVERAGES )

Surface air temperature	?? °C	(control	13.4)
Total precipitable water	?? mm/day	(control	3.09)
Total cloudiness	?? %	(control	51.6)
Outgoing long-wave 	?? W/m2	(control	-50.8)
Planetary Albedo	?? %	(control	30.5)